Thread cutting device



Dec. 1, 1964 L. J. CHAMBON 3,159,070

THREAD CUTTING DEVICE Filed July 13, 1962 6 Sheets-Sheet l Dec. 1, 1964L. J. CHAMBON 15 THREAD CUTTING DEVICE Filed July 13, 1962 SSheets-Sheet2 Dec. 1, 1964 L. J. CHAMBON THREAD CUTTING DEVICE 6 Sheets-Sheet 3Filed July 15, 1962 Dec. 1, 1964 L. J. CHAMBON mam CUTTING navrcs 6Sheets-Sheet 4 Filed July 13, 1962 d m w Q Q U .3 42 74/ 1 n U m mmm. Hmfi fl r L N mm cm m g ////&7 Y

. 2 m nw @Q ew a 6 3 3 Wm fifiomnrmw 3 3 Q l, 1964 L. J. CHAMBON THREADCUTTING DEVICE s SheetS- -Sheet 5 Filed July 13, 1962 L J. CHAMBON3,159,070

THREAD CUTTING DEVICE 6 Sheets-Sheet 6 Filed July 13, 1962 United StatesPatent 3,159,070 THREAD UTTING DEVECE Louis Jean Chamhon, Paris, France,assignor to Societe dEtudes de Machines peciaies, Paris, France FiledJuly 13, 1962, Ser. No. 289,567 Claims priority, application France,July 25, 1961,

868,949, Patent 1,303,073 1 Claim. (Cl. 83-321) This invention relatesto thread cutting devices.

As a rule, webs or sheets of different materials, notably paper, are cutby means of threads either in a flat-operating high-power press, or withthe assistance of a cylinder or an oscillating bed rolling withoutsliding on the cutting form or pattern.

In either case the presser member must be relieved to permit the feedingof the Web or sheet to be cut, together with intermittent control meansproducing inertia stress attaining in many cases considerable valueswhereby the rate of operation of the machine must be reduced.

Rotary cutting devices are also known wherein the cut ting unitcomprises two cylinders, one cylinder carrying cutters or blades cuttingby pressure on the other cylinder constituting the counterpart. Thesedevices are costly and fragile for the threads are machined directly inthe cylinder material. When the threads are Worn or damaged the completecylinder has to be replaced. On the other hand, this rotary cuttingdevice is capable of operating at relatively high speeds because theinertia of the moving members is very low.

0n the other hand, sheet printing devices are also known wherein theprinting blocks are moved in planes parallel to themselves along aclosed path comprising two parallel rectilinear portions interconnectedat their ends by two curved sections. During their movement, theprinting blocks travel through the gap formed between a printingcylinder and a counter-pressure cylinder, the sheets to be printed beingcarried along around the periphery of the presser cylinder.

It is the object of this invention to provide a thread-type cuttingdevice operating according to the basic principle of the printingapparatus of the type mentioned in the preceding paragraph, but designedfor cutting continuous webs.

To this end, this invention provides a device for cutting a continuousweb by means of threads, this device being characterized in that itcomprises in combination means for moving along a closed curvilinear andrectilinear path flat cutting blocks provided with cutting threads, andfor maintaining these blocks parallel to themselves during their travel,whereby they move between a presser cylinder and a counter-pressurecylinder, and means actuated intermittently for holding the web againstmotion when no block is present in proper cutting position between saidcylinders, and on the contrary releasing said web when a cutting blockis engaged between said cylinders.

The device according to this invention is advantageous in that themanufacture of the cutting blocks is relatively simple, notably throughthe use of cutting threads inserted in a wooden or like block. The costof these blocks is therefore very low.

On the other hand, as the cutting blocks travel continuously, no suddenvariation in the inertia of the moving component elements can takeplace.

In order to afiord a clearer understanding of the pre ent invention andof the manner in which the same may be carried out in practice,reference will now be made to the accompanying drawings illustratingdiagrammatically by way of example a typical embodiment of a deviceconstructed according to the teachings of the invention. In thedrawings:

FIGURE 1 is a longitudinal section showing the device during the cuttingof a web.

FIGURE 2 is a longitudinal section similar to FIG. 1 but showing thedevice between two cutting steps, the Web feed device being omitted fromthis figure.

FIGURE 3 is a simplified elevational view showing the differentcomponent elements of the kinematic arrangement.

I FIGURE 4 is a cross section taken upon the line IV-IV of FIG. 1.

FIGURE 5 is a cross section taken upon the line VV of FIG. 1. 1

FIGURE 6 is a cross section taken upon the line VI-VI of FIG. 1.

The device according to this invention comprises a frame structure 1consisting essentially of a. pair of side plates. The cutting blocksdesignated generally by the reference numeral 2 have a substantiallyflat configuration and comprise a plate 2a carrying a bed plate 25adapted to receive the threads 2c. Each block 2 is secured on a pair oflateral racks 3, 4 having their teeth out in the upper and lower facesas shown at 311, 3b and 4a, 45 respectively. Racks 3, 4 areinterconnected through a pair of cross members 5 so as to constitute arigid frame and rigid with lateral guide members 38.

These racks 3, 4 are driven by pinions 6 during the rectilinear portionof the travel of the cutting blocks 2. These cutting blocks are alsodriven along curved paths, while rema ning parallel to each other, bythree pairs of notched wheels 7, 8 and 9; each wheel 7-9 has formedtherein a pair of notches 7a, 8a, 9a spaced 180 from each other. Thepair of wheels 7, 9 are disposed symmetrically in relation to the axisof the pair of central wheels 8.

The aforesaid pinions 6 are rigid with shafts 10 rotatably driven fromthe main power shaft 11 of the machine (see FIG. 3) through trains ofgears 12, 13, 14, 15, 16, 17, 6a on the right-hand side, and 12, 13, 14,15, 18, 20, 6a on the left-hand side.

The right-hand and left-hand notched wheels 7, 9 are rotatably mountedin overhanging relationship on spindles 21 rigid with the framestructure 1 of the machine in order to free the passage for the cuttingblocks 2 during their movement of rotation. The notched wheels 7, 9 arerigid with pinions 22 and rotatablyjdriven from the power shaft 11 (FIG.3) through trains of gears 12, 13, 14, 15, 16, 1'7, 23, 22 for theright-hand wheel '7, and 12, 13, 14, 15, 18, 20, 24, 22 for theleft-hand wheel 9.

The two central wheels 8 are rotatably mounted on hollow spindles 25rigid with the frame structure 1. They are rigid with pinions 19 androtatably driven from the power shaft 11 through trains of gears 12, 13,14, 15, 16, 17, 13a and 19.

The racks 3 and 4 carry each at their two longitudinal ends a pair ofrollers 25, 29 journalled on a common shaft and, substantiallyintermediate their ends, a roller 2% located in the same longitudinalplane as the rollers 29.

The racks 3 and 4 are rotatably driven through the rollers 26 engagingthe notches 7a, 8a, 9a of the notched wheels 7, S, 9.

A central switching device is provided for assisting the rollers 26 intheir driving engagement with the notches 8a of the central wheel 8 toensure the movement guide members are pivoted on pins 28 and 28arespec-- tively.

The upper movable guide members 2'7 and lower movable guide members 2701are interconnected through links 70. Each upper movable guide member 27is rigid with a driven toothed segment 36 in meshing engagement withthereon a sleeve 7e having. a pair of arm extensions 77, "78 carryingfollowers in the form of rollers 79 and 9% bearing on cams 73 and 73a.

The racks 3and 4 are guided in the longitudinal direction by rollers 22?and 29a disposed between the upper rails-3ti and the central rails 31,32, 33, 34 at the upper portion and between the lower rails 35 and central rails 31, 32, 33, 34 at the lower portion during the rectilineartravel.

During the movement of rotation (see 1 16.2) the racks are guided bycurved rails 36 at the two longitudinal ends of the raceway. i V a Theracks 3, 4 are guided in the transverse direction by rollers 37journalled on pins carried by the upper rails 34} and lower rails 35,engaged by the lateral guide members 38 rigidwith racks 3 and 4.

The cutting blocks 2 secured on racks 3, 4 travel .through the gap leftbetween the cylinders 39 and as.

The lower or presser cylinder 39 is rigid with the power shaft 11 andrevolves at a constant angular speed.

The peripheral speed of this cylinder 39, which has a diameter equal tothe pitch diameter of pinion T2,. 7

equals the linear speed of racks 3, 4 and therefore the velocity oftranslation of the cutting blocks 2. The developed or peripheral lengthof cylinder 39 equals the distance between the axes ofthe right-hand andlefthand notched wheels '7, 9, plus the length of the circumference atthe pitch circle of a toothed wheel, this pitch circle having a diametercorresponding to half the distance between the wheels 7 and 9 and to thediameter of the pitch circle of pinions 1? and '22. The central wheel 3is equaly spaced from wheels 7 and 9.

The upper or counter-pressure cylinder 4% is rigid with pinion 15 androtatably driven from the power shaft 11 through a train of gears 12,13, 14, 15 the pitch circle of pinion 15 having the same diameter assaid cylinder 40. Thus the latter is driven at a peripheral speed equalto that of cylinder 39 and also to the linear speed of the cuttingblocks 2. p

The vertical position of shaft 11 may be altered through any suitablemeans to permit the adjustment of the; gap left between cylinders 3% and40 as a function of the thickness of the cutting blocks 2.

To this end the shaft 11 may be carried, as shown, by eccentric sockets41, 42 held against motion in the position corresponding to the desiredgap between cylinders 39 and 40. Of course, any other suitable means maybe used for varying the vertical position of shaft 11.

The web-43 to be cut is delivered in a predetermined size by a pair offeed cylinders td, 45 revolving at a constant angular speed andimparting therefore a constant linear speed to the Web, this speed beingin any case constantly-lower than the linear speed of the thread cuttingblocksZ.

The device'comprises on the other hand two pairs of web-receivingcylinders, that is, cylinders 46, 47 on the. one hand and cylinders 48,49 on the other hand. The shafts 46a and 48a of the lower cylinders 46and 43 (FIG. 3) are rigid with pinions 5t and 51, respectively, and thediameter of these cylinders is equal to the pitch diameter of thesepinions. Cylinder 46 is rotatably driven from the main power shaft 11through the train of gears 12, 52, 54B. Cylinder i8 is rotatably drivenfrom the left-hand wheel 9 through the train of gears 22, 53, 54, 51.The upper cylinders 47 and 49 are carried by arms 55 and 56,respectively, these arms being pivoted on the framestructure l of thedevice by means of pins 55a and Sea, respectively. The web receivingcylinders 46, 4 7,48, 49 revolve at a peripheral speed equal to thelinear speed of cut-ting blocks 2, due to the transmission ratiosobtaining between the pinions.

Thedevice further comprises, on the web feed side, a set of clip arms 57pivoted on a pin 58 carried by the frame of the device. These clip arms57 are adapted to either engage a tray 59 over which the web 43 iscaused to slide, or bemoved away therefrom.

The movement of these clip arms 57 is controlled cyclically through anysuitable means, whether of mechanical, pneumatic, electronic or electrictype, in order to discontinue the feed movement of web 43 through theapparatus during the time intervals in which no cutting block 2 is fedbetween the cylinders 39 and iii. In the specific form of embodimentillustrated, themovement of clip arms 57 is con-trolled by a pair ofcams 69, 61 mounted on a shaft 62 rigid with pinion 52 having a pitchdiameter equal to half that of pinion 12. These cams 6t), 61 are engagedby a roller follower 63 carried by the end of an arm rigid with shaft58.

Each cam 66, .61 comprises a segment of smaller diameter and a segmentof greater diameter, and they are adapted to be shifted angularly fromeach other. Thus, the time period during which the clip arms 57 releasethe web 43 can be varied at will,*that is, as a function of the papersize contemplated.

The device, according to this invention operates as follows: 7

As long as no cutting block 2 is in its operative position between thecylinders 39 and 4% (that is, when the blocks 2 are rotating) the cliparms 57 hold the web 43 against longitudinal motion. During theinitialportion of the block translation, when the first cutting blockengages the gap left between the cylinders 3% and 4t and the cuttingthreads of this block engage the presser cylinder 3%, the cams 6t), 61set for this purpose cause the rotation of lever 64 to raise the cliparms. 57 off the web. Thus, the latter is free to move at the desiredlinear speed through the device. This is permitted by the fact that theweb 43, which is held against motion during the rotation of blocks 2develops a loop 43a of variable length between the feed cylinders 44, 45and the first pair of web-receiving cylinders 4d, 47. This loopincreases when the clip arms 5'7 discontinue the delivery of web tothe'cutting device, and

5 the Web against motion through the clip arms 57.

-Then the loop 43a increases again, the clip arms 57 holding the web 3until the next cutting block is positioned for accomplishing itsrectilinear stroke.

After having been cut by the threads on the cutting blocks, the web isfed to a rotary decorticating or like device of known'type (not shown).I

Of course, the specific form of embodiment shown hereinabove withreference to the accompanying drawings should not be construed aslimiting the invention as it is given by way of example only; thus, manymodifications and alterations may be brought thereto without departingfrom the spirit and scope of the invention as set forth in the appendedclaim.

What I claim is:

A device for cutting a continuous web by means of threads, whichcomprises in combination a power shaft,-

a presser cylinder and a counter-pressure cylinder disposed parallel toeach other so as to leave a constant gap therebetween, means forcontinuously rotatably driving said presser and counter-pressurecylinders from said power shaft, at least one flat thread-carryingcutting block, means driven from said power shaft for moving said fiatcutting block unidirectionally along a closed curved path and throughsaid gap while keeping said block parallel to itself during its travelthrough said gap, means for feeding said web into said gap between saidcylinders a stationary bed plate over which said web is caused to slidein advance of said g-ap, a pin extending transversely to the directionof feed of said Web, a clip arm pivoted on said pin and adapted toengage said bed plate, and means controlled cyclioally from said powershaft for lowering said clip arm toward said bed plate until saidcutting block begins to travel through said gapbetween said pressercylinder and said counter-pressure cylinder for the purpose of grippingsaid web between said clip arm and stationary bed plate and therebyholding said web against motion and subsequently raising said clip armwhen said block engages said gap.

References Cited by the Examiner UNITED STATES PATENTS 528,830 11/94Vierengel 1 01-486 FOREIGN PATENTS 11/58 Canada.

OTHER REFERENCES Germany, Sch. 11,519, Aug. 16, 1956. WILLIAM w. DYER,JR., Primary Examiner. ANDREW R. JUHASZ, Examiner.

